Coauthor Ari Friedlander deploys a multi-sensor suction cup tag on a blue whale off the coast of California.
Elephant populations continue to dwindle in Tanzania.
With proper safeguards, water currents can be harnessed out of sight.
Barely pulled back from the brink of extinction, California condors are still being poisoned by lead-based ammunition.
Vulnerable everywhere in the wild, lions already face regional extinction.